JPH0215748B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a valve body in which a spherical valve is disposed within a valve body forming a fluid inlet and an inlet, and a spherical valve is disposed at the inner end of the fluid inlet and outlet to prevent fluid leakage. By sandwiching the spherical valve between the valve seats, engaging the inner end of a rotatably operated valve stem on the valve body, and operating the outer end of the valve stem. This invention relates to the operating position of a spherical valve in which a spherical valve element is rotated between a valve open position and a valve closed position.

[Conventional technology]

BACKGROUND ART Conventionally, for city gas piping, etc., a pit construction method has generally been adopted in which a pit is installed underground so that valves can be directly accessed and serviced when necessary. However, because they are shared with other underground facilities (water, electricity, telephone, sewage, etc.), instead of the pit construction method, which requires a large space, pipes and valves are buried directly underground. In addition to preventing oxygen deficiency and safe operation by installing pipes that extend to the ground and operating valves from the ground without entering the pit, simple pits that do not require maintenance have come into use. This simple pit is also economically superior.

The present invention particularly relates to an operating device for such a directly buried spherical valve.

Moreover, this valve is also fully satisfactory for use in above-ground piping.

In such a spherical valve, a spherical valve element is placed inside a valve body that forms a fluid inlet and is sandwiched between valve seats placed at the inner end of the fluid inlet and outlet to prevent fluid leakage. , adapted to rotate the spherical valve between a valve open position and a valve closed position by manipulating the outer end of a valve stem that engages the spherical valve at its inner end; If the valve seat is always kept in pressure contact with the valve element, the operation is not only difficult, but the valve seat is easily damaged, and the valve seat deforms in a short period of time, making it impossible to achieve the desired effect.

In order to eliminate this drawback, the above-mentioned valve seat is attached to the inner end of a piston that is slidably provided within the valve body, and pressure fluid is sent behind the piston to push the piston toward the spherical valve. A spherical valve has been proposed in which a conduit for conveying pressurized fluid is formed within the valve body so that the valve seat is pressed against a spherical valve element.

In such a spherical valve, when the valve is opened, pressure fluid is not sent behind the piston, and the valve seat is not pressed against the spherical valve element, so that the spherical valve element can be easily operated and the valve is closed. Pressure fluid can be sent behind the piston to force the valve into contact with the spherical valve element to prevent fluid leakage.

[Problem that the invention seeks to solve]

The structure of the spherical valve operating device as described above requires a pressure medium circuit for introducing pressure medium into the valve body in order to move the piston that moves the valve seat. When using such a spherical valve as an underground type, a conduit for sending pressure fluid behind the piston for moving the valve seat must be built outside the valve body of the spherical valve. In such a structure in which the pressure medium circuit is provided outside the valve using a separate pipe, the workability of directly burying the valve is extremely poor and maintenance is difficult.

The present invention aims to solve the problems in a spherical valve operating device that eliminates these drawbacks.

[Means for Solving the Problems] As a means for solving the above-mentioned problems, the present invention disposes a spherical valve inside a valve body forming a fluid inlet and an inner part of the fluid inlet to prevent fluid leakage. The spherical valve element is sandwiched between valve seats disposed at the ends, the inner end of a valve stem rotatably provided on the valve body is engaged with the spherical valve element, and the outer end of the valve stem is engaged with the spherical valve element. In a spherical valve operating device which rotates a spherical valve element between a valve open position and a valve closed position by operation, the above-mentioned valve seat is mounted inside a piston that is slidably provided within the valve body. a conduit for conveying pressurized fluid into the valve body for driving the pressure fluid behind the piston to force the piston toward the spherical valve and to press the valve seat against the spherical valve; The end of the conduit leads out of the valve body through the center of the shaft around which the valve stem rotates, connects it to a pressure fluid supply source, and supplies pressure medium behind the piston. A shielding plate is provided in the middle of the sending pipe line to be rotated together with a nozzle and a valve stem fixed to the valve body, and the shielding plate is rotated in close contact with the nozzle,
The present invention provides a spherical valve operating device characterized in that a conduit for transmitting a pressure medium is opened only when a valve stem is rotated to a valve closed position.

[Function] According to the present invention, the circuit for conveying the pressure fluid that presses the valve seat against the spherical valve element is formed completely within the valve body, and the pressure fluid flows through the rotation shaft that rotates the valve stem for opening and closing the valve. Since it is only necessary to connect the outside through the center to the pressure supply source, the work efficiency during direct burial is good, and maintenance can be easily performed. However, according to the configuration of the present invention, a shielding plate is provided which is rotated together with the nozzle and the valve stem fixed to the valve body, and the shielding plate rotates in close contact with the nozzle, and the valve stem is in the valve closed position. The pipe for sending pressure medium is opened only when the valve body is rotated, so when the valve body is rotated to the valve-closed position, pressure fluid is sent to press the valve seat against the spherical valve, thereby controlling the opening and closing of the valve. The spherical valve can be rotated lightly, and when the valve is closed, the valve seat is pressed against the spherical valve to prevent fluid leakage, and when the valve is open, pressurized fluid is accidentally sent to the valve seat. This prevents the valve from being crimped onto the valve.

〔Example〕

Hereinafter, drawings showing embodiments of the present invention will be described. In the figure, 1 is the valve body, 2 is a spherical valve element that can be rotated between the valve open position and the valve closed position within the valve body, 3 is the valve stem that rotates the spherical valve element, 4 is a gland part,
5 indicates a valve seat that is pressed onto the spherical valve to prevent fluid leakage.

According to the present invention, the valve seat 5 is attached to the inner end of the piston 6 slidably provided at the inner end of the fluid inlet and outlet provided in the valve body, so that the valve seat 5 is always separated from the spherical valve 2. A conduit 7 is provided in the valve body for conveying a pressure medium behind the piston 6 to press the valve seat 6 onto the spherical valve 2 when necessary. the upper part 7' of this conduit.
The valve stem 3 for rotating the spherical valve element 2 is led out through the center of the rotating shaft 8, and connected to a pressure fluid supply source.

In the figure, 9 is a stopper provided to restrict the rotation of the rotating shaft 8 to an angle of 90 degrees, 10 is a pressure medium abnormal pressure relief valve, and 11 is a block plate, etc. that opens and closes the supply of pressure medium, or in case of emergency. This shows a valve that prevents the flow from blowing out when the flow pressure backflows due to an abnormality. In this way, the pressure medium passes through the center of the axis of rotation 8 of the valve and
is sent behind the piston 6 through conduits 7, 7';
By pressing the piston, the valve seat can be pressed against the valve element. Further, the pressure medium is sent to the gland section 4 through the gap 12 to prevent leakage in this section. Also,
According to the present invention, a nozzle 13 attached to the valve body and a shielding plate 14 fixed to the valve stem 3 and rotating together with the nozzle 13 are provided in the middle of the pipe line 7 for sending pressure medium behind the piston. The closing plate 14 rotates in close contact with the nozzle 13, and the closing plate 14 is provided with a hole 15 so that only when the valve operating shaft is rotated to the valve closing position, 15 communicates with the nozzle 13 to release pressure. It is now possible to send media.

As described above, the pressure medium entering from above the rotating shaft 8 enters the chamber above the valve stem 3, passes through a passage (not shown) provided in the valve body, and is shielded from the chamber inside the valve body. It is sent through the hole 15 in the plate 14, the nozzle 13 and the line 7 to the chamber behind the piston 6.

Therefore, it is avoided that pressure medium is fed and pressurizes the valve seat 5 against the valve element 2 when the valve is in the open or intermediate position.

As mentioned above, in the above-mentioned spherical valve, the valve seat is kept away from contact with the valve element at all times, and is pressed against the valve element only when necessary by sending pressure medium behind the piston, so that the valve seat is not in contact with the valve element. At the time of opening and closing, the pressure of the pressure medium sent to the back of the piston 6 supporting the valve seat 5 is released to separate the valve seat 5 from the valve element 2, and then the valve element 2 is opened and closed. Therefore, during the opening and closing operations of the valve, the valve is opened and closed lightly, and damage to the valve seat is prevented, so the valve seat is prevented from deforming in a short period of time and becoming unusable. . Furthermore, since the pressure medium can also be injected into the gland, leakage from the gland can be prevented, and sealing performance can be maintained and improved by tightening the packing and the gland.

As mentioned above, in the present invention, the pressure medium circuit for crimping the valve seat is built into the structure of the valve,
Since the valve stem is operated by introducing a pressurized medium from the center of the circuit axis, there is no need to provide a separate pipe for pressurizing the valve seat. In addition, construction is simple and operation, maintenance, and management are easy. Furthermore, when separate piping is provided as in the past, problems such as natural corrosion and electrolytic corrosion occur, but in the present invention, such concerns are completely unnecessary.

In addition, the action of the blocking plate provided in the middle of the pipeline for supplying the pressure medium prevents the pressure medium from being erroneously sent when the valve is opened and pressing the valve seat against the valve element.

[Brief explanation of drawings]

The drawing shows a cross-sectional view of the device according to the invention. 1... Valve body, 2... Spherical valve, 3... Valve stem,
4...Gland part, 5...Valve seat, 6...Piston, 7...Pipe line, 8...Rotating shaft, 9...Stopper, 10...Relief valve.

Claims (1)

[Claims] 1. A spherical valve element is placed within a valve body that forms a fluid inlet and outlet, and the spherical valve element is sandwiched between valve seats placed at the inner end of the fluid inlet and outlet to prevent fluid leakage, and the spherical valve element is inserted into the valve body. The inner end of a rotatably provided valve stem is engaged with the spherical valve element, and the outer end of the valve stem is operated to rotate the spherical valve element between a valve open position and a valve closed position. In the operating position of the spherical valve, the valve seat is mounted on the inner end of a piston slidably disposed within the valve body, and pressure fluid is pumped behind the piston to cause the piston to become a spherical valve. In order to press the valve seat toward the spherical valve element, a conduit for conveying pressure fluid is formed in the valve body, and the end of the conduit is connected to the shaft of rotation that rotates the valve stem. It is led out of the valve body through the center, connects it to a pressure fluid supply source, and is rotated together with a nozzle and a valve stem fixed to the valve body in the middle of a conduit that sends the pressure medium behind the piston. a shielding plate is provided, the shielding plate rotates closely with the nozzle;
A spherical valve operating device characterized in that a conduit for transmitting pressure medium is opened only when a valve stem is rotated to a valve closed position.